NERVOUS SYSTEM OF AVES. 127 



dips above tlie gastrocnemii muscles^ and runs tlirongli tlie same 

 ligamentous pulley that transmits the tendon of the biceps muscle, 

 ib. 41 ; it then detaches some large filaments to the muscles on 

 the anterior part of the leg, under which it divides into two 

 branches, which proceed close together, in company with the 

 anterior tibial artery, to the fore part of the ankle-joint, at which 

 place they separate ; one passes superficially over the outer part 

 of the joint, the other goes first under the transverse ligament 

 which binds down the tendon of the tibialis anticus muscle on the 

 tibia, and then over the inner part of the joint, below which it 

 divides into two branches : the one is distributed to the inner side of 

 the metatarse, and the tibial side of the back toe, /, and the next 

 toe ; the other turns toward the centre of the metatarsal bone, 

 and penetrates the tendon of the tibialis anticus just at its inser- 

 tion, and then rejoins the branch of the peroneal nerve it accom- 

 panied down the leg. They continue their course together again 

 in the anterior furrow of the metatarsal bone ; and at the root of 

 the toes, separate once more, and proceed to the interspaces of 

 the three anterior toes, and each divides into two filaments, which 

 run alono; the sides of the toes to the claw. 



§ 139. Sympathetic System, — The superior cervical ganglion is 

 connected with the glossopharyngeal nerve more closely in some 

 birds than in others : it communicates by branches with the 

 portio dura and second di^'ision of the fifth, and supplies the 

 lacrymal gland : a second branch accompanies the entocarotid, 

 supplies the harderian gland, and communicates with the first 

 division of the fifth. ^ The " cervical portion " of the sympathetic 

 may be compared with that in the Snake in its not having a chord 

 or prolongation accompanying the trunk of the par vagum ; it, 

 however, corresponds in some measure also with that of the 

 Turtle, for in the Swan a branch is continued down the neck 

 with each carotid artery, and in its course communicates several 

 times with its fellow.' ^ ' In the Pelican the carotid is a single 

 trunk dividing into two at the upper part of the neck ; a branch 

 passes from the superior cervical ganglion with each of these, and 

 becomes united into one near their bifurcation; it gives off 

 branches for the supply of the carotid, and to communicate with 

 the prolongation accompanying the vertebral artery : at the bottom 

 of the neck it dips down in the median line between the anterior 

 cervical muscles, and divides into two branches, each joining the 

 penultimate cervical ganglion.' ^ The sympathetic passes down 



' Liv. '' lb. p. 104. 



